154 research outputs found
T. Gonzalez, O.M. Bulashenko, J. Mateos, D. Pardo, L. Reggiani and J.M. Rubi "Noise suppression due to long-range Coulomb interaction: crossover between diffusive and ballistic transport regimes", Semicond. Sci. Technol. {\bf 12}, 1053-1056 (1997).
No full textT. Gonzalez, O.M. Bulashenko, J. Mateos, D. Pardo, L. Reggiani and J.M. Rubi, "Shot-noise suppression in mesoscopic structures due to long-range Coulomb interaction" Proc 10th Int. Conf. on Nonequilibrium CarrierDynamics in Semiconductors, Berlin 1997, Phys. Stat. Sol. (b),{\bf 204}, 450-452 (1997).
No full text
Effect of dimensionality on shot-noise suppressionin nondegenerate diffusive conductors'
No full textEffect of long-range Coulomb interaction on shot-noise suppression in ballistic transport
No full textWe present a microscopic analysis of shot-noise suppression due to long-range Coulomb interaction in semiconductor devices under ballistic transport conditions. An ensemble Monte Carlo simulator self-consistently coupled with a Poisson solver is used for the calculations. A wide range of injection-rate densities leading to different degrees of suppression is investigated. A sharp tendency of noise suppression at increasing injection densities is found to scale with a dimensionless Debye length related to the importance of space-charge effects in the structure
Microscopic analysis of shot-noise suppression in nondegenerate diffusive conductors
No full textWe present a theoretical investigation of shot-noise suppression due to long-range Coulomb interaction in nondegenerate diffusive conductors. Calculations make use of an ensemble Monte Carlo simulator selfconsistently coupled with a one-dimensional ~1D! Poisson solver. We analyze the noise in a lightly doped active region surrounded by two contacts acting as thermal reservoirs. By taking the doping of the injecting contacts and the applied voltage as variable parameters, the influence of elastic and inelastic scattering in the active region is investigated. The transition from ballistic to diffusive transport regimes under different contact injecting statistics is analyzed and discussed. Provided significant space-charge effects take place inside the active region, long-range Coulomb interaction is found to play an essential role in suppressing the shot noise at qU@k BT. In the elastic diffusive regime, momentum space dimensionality is found to modify the suppression factor g, which within numerical uncertainty takes values respectively of about 1/3, 1/2, and 0.7 in the 3D, 2D, and 1D cases. In the inelastic diffusive regime, shot noise is suppressed to the thermal value
Electron-number statistics and shot-noise suppression by Coulomb correlation in nondegenerate ballistic transport
No full textWithin a Monte Carlo simulation, we investigate the statistical properties of an electron flow injected with a Poissonian distribution and transmitted under ballistic regime in the presence of long-range Coulomb interaction. Electrons are shown to exhibit a motional squeezing which tends to space them more regularly rather than strictly at random, and to evidence a sub-Poissonian statistics with a substantially reduced Fano factor Fn!1. The temporal ~anti!correlation among carriers is demonstrated to be a collective effect which persists over the transit of several successive electrons, and results in a considerable ~more than one order of magnitude! shot-noise suppression
Universality of the 1/3 shot-noise suppression factor in nondegenerate diffusive conductors
No full textShot-noise suppression is investigated in nondegenerate diffusive conductors by means of an ensemble Monte Carlo simulator. The universal 1/3 suppression value is obtained when transport occurs under elastic collision regime provided the following conditions are satisfied: (i) The applied voltage is much larger than the thermal value; (ii) the length of the device is much greater than both the elastic mean free path and the Debye length. By fully suppressing carrier-number fluctuations, long-range Coulomb interaction is essential to obtain the 1/3 value in the low-frequency limit
Effects of the epitaxial layer thickness on the noise properties of Schottky barrier diodes
No full textAn analytical theory to describe the combined effects of the epitaxial layer thickness and the ohmic contact on the noise properties of Schottky barrier diodes is presented. The theory, which provides information on both the local and the global noise properties, takes into account the finite size of the epitaxial layer and the effects of the back ohmic contact, and applies to the whole range of applied bias. It is shown that by scaling down the epitaxial layer thickness, the current regime in which the noise temperature displays a shot-noise-like behavior increases at the cost of reducing the current range in which the thermal-noise-like behavior dominates. This improvement in noise temperature is limited by the effects of the ohmic contact, which appear for large currents. The theory is formulated on general trends, allowing its application to the noise analysis of other semiconductor devices operating under strongly inhomogeneous distributions of the electric field and charge concentrations
Quantum suppression of shot noise in field emitters
No full textWe have analyzed the shot noise of electron emission under strong applied electric fields within the Landauer-Bttiker scheme. In contrast to the previous studies of vacuum-tube emitters, we show that in new generation electron emitters, scaled down to the nanometer dimensions, shot noise much smaller than the Schottky noise is observable. Carbon nanotube field emitters are among possible candidates to observe the effect of shot-noise suppression caused by quantum partitioning
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